Related Experiment Video
Updated: Dec 5, 2025
Author Spotlight: Exploring the Long-Term Health Impacts of Intracytoplasmic Sperm Injection on Offspring
Published on: May 17, 2024
Is conception by in vitro fertilization associated with altered antenatal and postnatal growth trajectories?
Steve Turner1, Eilidh Maclean1, Smita Dick1
1Child Heath, Royal Aberdeen Children's Hospital, University of Aberdeen, Aberdeen, United Kingdom.
Insights
Children conceived via fresh embryo transfer (ET) and frozen-thawed embryo transfer (FET) show different early growth patterns compared to natural conception (NC). These differences in fetal growth trajectories and birth size may not persist by age 5.
Area of Science:
- Reproductive Medicine
- Pediatric Growth and Development
- In Vitro Fertilization
Background:
- Assisted reproductive technologies like fresh embryo transfer (ET) and frozen-thawed embryo transfer (FET) are increasingly common.
- Understanding the long-term growth implications for children born after these procedures is crucial.
Purpose of the Study:
- To compare growth trajectories from the first trimester to five years of age.
- To assess differences between children conceived via fresh ET, FET, and natural conception (NC).
Main Methods:
- A historical cohort study analyzed data from children born between 1997 and 2012.
- Measurements included fetal size (trimesters 1-3), birth size, and size at 5 years.
- Comparisons were made between NC (n=65,683), fresh ET (n=576), and FET (n=179) groups.
Main Results:
- First-trimester crown-rump length was longer in fresh ET compared to NC.
- Second-trimester head size was larger in both fresh ET and FET groups versus NC.
- Birth weight was lower after fresh ET compared to FET, but no weight differences were observed at 5 years.
Conclusions:
- In vitro fertilization (IVF) is associated with altered antenatal growth trajectories in the first and second trimesters.
- Differences in fetal growth and birth size between IVF and NC persist, but their long-term significance is unclear.
- Larger prospective studies are needed to fully understand the implications of these findings.
Objective:
To study whether the growth trajectory of the first, second, and third trimester, birth, and 5 years of age differs between children born following fresh embryo transfer (fresh ET), frozen-thawed embryo transfer (FET), and children born after natural conception (NC).
Design:
Historical cohort study of children. The analysis compared cross-sectional and longitudinal differences in measurement between individuals stratified by method of conception.
Setting:
Not applicable.
Patients:
Participants were born between 1997 and 2012 by NC (n = 65,683), fresh ET (n = 576), and FET (n = 179). Data were available for method of conception and fetal, maternal, and neonatal characteristics and measurements at 5 years.
Intervention (S):
None MAIN OUTCOME MEASURE(S): Size at first, second, and third trimester, birth, and 5 years.
Result(S):
In the longitudinal model, first trimester crown-rump length was significantly longer after fresh ET compared to NC. Second trimester head size was larger after fresh ET and after FET compared to NC. Birth weight was lower after fresh ET conception compared to FET. At 5 years of age, children conceived by fresh ET and FET were no heavier than peers conceived by NC.
Conclusion(S):
Individuals conceived by in vitro fertilization have significantly different antenatal growth trajectories during the first and second trimester compared to those conceived by NC, and differences persist at birth for weight and head size. The relevance of these different growth trajectories remains uncertain, and larger prospective studies are required.
More Related Videos
Related Concept Videos
01:24In Vitro Fertilization
The IVF process begins with ovarian stimulation, during which reproductive endocrinologists prescribe hormonal medications to stimulate the ovaries to produce multiple eggs instead of the single...
01:07Teratogenicity
01:10Nature and Nurture
01:38Fertilization